Most of us probably aren't envisioning the Dune hunter-seeker being developed from this, but even a simple cavity resonator would make it a weapon beyond defending against: https://en.wikipedia.org/wiki/The_Thing_(listening_device)

But it's within the abilities of a hobbyist to build a dragonfly-sized drone with video capabilities. It's not beyond the realm of imagination that a mosquito-sized one could be built by entities who have real funding.